Skulpt loads on first run (~1 MB). Code stays in your browser and is not sent to the server.
What works / what does not
✓ print, variables, strings, math, booleans✓ if/elif/else, while, for, range✓ def, return, built-ins like len/sum✓ lists, dicts, tuples (basics)✗ pip, third-party packages✗ reading/writing real files✗ network, urllib beyond basics✗ numpy, pandas, full stdlib
Skulpt is a browser subset of Python 3 — great for chapter 1–2, not for production or data science.